1. Field of the Invention
This invention relates to electrical connectors, and more particularly, to grounding lugs and connections for receptacles and clamps. In order to reduce the possibility of electrical shock, various electrical wiring systems, receptacles, switches and the like are required to be connected to ground. Most devices currently in use for making these ground connections are relatively difficult and time-consuming to use. The present invention, however, provides for quick and easy connection to ground.
2. Prior Art
There are numerous devices in the prior art for making ground connections in electrical wiring systems, including lay-in type grounding lugs as exemplified in U.S. Pat. Nos. 3,492,625, 4,159,859, 4,199,216, 4,248,490 and 4,355,852, and receptacle grounding clips as exemplified in U.S. Pat. Nos. 3,786,399, 3,885,847 and 4,392,012. The lay-in grounding lugs facilitate connection to electrical raceways and enable a ground wire to be connected between its ends with a device without requiring the ground wire to be threaded through or fed end-wise through the ground connection. The receptacle grounding clips establish a ground connection between an electrically conductive strap of an electrical receptacle to an electrically conductive mounting box.
Grounding lugs currently in widespread use on electrical receptacles comprise an electrically conductive body having a flange or foot thereon for attachment to the back plate of the receptacle by a screw extended therethrough, and an opening therethrough through which the ground wire is extended or threaded for attachment to the ground socket. This maneuver is difficult and time-consuming to accomplish and increases the cost of performing wiring services in residential and commercial installations.
All of the lay-in grounding lugs disclosed in the aforementioned patents relate to devices for coupling and grounding an electrical raceway and an electrical box to which it is assembled. These patents describe various structures, all essentially having a U-shaped portion into which a ground wire is laid and a screw for threading against the wire. None of these patents discloses or suggests a lay-in grounding lug which is constructed or suitable for use with an electrical receptacle for establishing a ground connection between the back plate and ground socket of the receptacle.
The patents disclosing grounding clips for electrical receptacles all teach separate clip devices which are connected between a grounding strap on the receptacle and the mounting box. None of them suggest the use of an existing assembly screw for holding in place the ground socket as a means for also establishing a ground connection between the receptacle back plate and ground socket. Moreover, none of these patents suggest an extension of the ground socket itself as a means of establishing a ground connection with the receptacle back plate.